Threading-machine.



` v v H. W. GSTER.

THRBADING MAGHINB.

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ente r 7?.' @4M *www mf Patented July 26, 1910.

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\ Lia/671 fal1 H. W. OSTER.

THREADING MACHINE.

APPLIOATION P ILED JUNE 1, 190s.

H. W. OSTER.

THBEADING MACHINE. ,K APPLIOATIQN FILED JUNE 1, 1eme.

Patented July 26, 1910.

3 SHEETS-SHEET 3.

seance.

HERMAN W.

OSTER, OF CLEVELAND, OHIO, ASSIGNOR TO THE OSTER MANUFACTURING COMPANY,OF CLEVELAND, OHIO, l.A CORPORATION OF OHIO.

THREADING-MACHINE.

Specication of Letters Patent. Patented July 26, figli).

Application led June 1, 1908. Serial No. 436,078.

To all whom it may concern:

Be it known that I, HERMAN W. OSTER, a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented a certain new and useful Improvement in Threading-Machines, ofwhich the following is a full, clear, and exact description.

This invention pertains to devices for cutting tapered threads uponcylindrical pipes and bars. It is speciically an improvement 'upon thetype of thread cutting devices which form the subject matter of my priorapplication No.'417,806, filed February 26, 1908.

The primary object of this invention is, however, to provide means bywhich, after a thread has been cut upon the work, the dies may bewithdrawn from engagement therewith, and so permit the work to beremoved from lthe device without having to turn the die-carrying part ofthe device backward.

Another object of the invention is to provide' efficient means forsecuringthe work to be threaded centrally within the device.

In the drawing, Figure 1 is an end view of a thread cutting deviceembodying the l invention. Fig. 2 is a side elevation thereof brokenaway at onepoint and there shown in section. Fig. 3 is a side elevationlargely in section showing the position of the parts when the cutting ofa thread is commenced. Fig. 4 is a sectional view of the lead ring; Fig.5 is a side elevationof that ring; and Fig. (3 is a view similar to Fig.3, but showing the position of the parts ater the threads have been cutand the dies withdrawn from engagement with the work.

Referring to the parts by letters, A represents the tubular work holderwhich is preferably made of two parts, a, a', rigidly fixed one upon theother. Upon the art a is an annular iange 1,2 between whic and the endof the part a' an annular groove is formed in which the ring E isrotatably mounted, but is held against endwise'movement.

B represents the tubular die carrier which has a long cylindricalportion b which is rotatably mounted in the member' A. rlhe dies C aremovable radially in guide ways in the end or the member B. A cam plate Dis rotatably mounted upon lthe member B,

land is held thereon by a flanged ring F which screws into the end ofthe member B. This cam plate has the usual cam ribs d on its inner facewhich engage in notches in the dies 1n the usual way, whereby, as thiscam plate is turned, the dies are simultaneously and equall moved in oroutin their guide ways. Thls cam plate is provided with an outwardlyextended portion d having init a hole cl2.

An arm G is fixed in an arcual slot e to the ring E, and extendstherefrom toward the end of the device at an inclination to the axis ofsaid ring,a`sshown. This arm passes through the hole d2 intheoverhanging part of thecam plate, and a cylindrical nut g which looselylits this hole is screwed onto this bar. Pins H secured to the ring E,are parallel with the axis of the device, and pass loosely through holesin the member B.

A ring K Vis fixed to the member B lying in a recess between said memberand the part a of the member A. In the periphery of this ring is agroove Ic, cut spirally with the same pitch as the pitch of the threadson the dies C. A radially extended spring actuated plunger M is mountedin the member A, and is adapted to be moved radially inwardby its springm, into the groove is.

In the member A, near the end thereof are three, more or less, radiallymoving clamping bars N having spiral grooves n in their outer faces,which are engaged-by spiral ribs 1' on a cam plate R rotatably mountedupon the member A, and thereon held by a lock ring P. A set screw Tscrews longitudinally through each of the bars N, and the points of saidscrews, which may be adjusted by turning the screws one way or theother, engage with the work.

Now, lto use this device, the `cylindrical pipe or bar to be threaded ispassed into the device from the right end thereof, where the parts arein the position shown in Fig. 3, until its end engages with the dies C.rlhe cam plate D has been turned .to properly set the dies; and the barG has been adjusted in the slot e in the ring E, so that the cylindricalvnut G, by its engagement with the cani plate in the hole cl2 therein,will `hold the cam plate and consequently the dies in the properposition for beginning the cutting of the threads. When the parts areyplunger M upon the spiral groove c in the ring K. In other words, thisring KandA plunger M serve the purpose of a lead screw when the cuttingof the thread is first begun. When, however, one revolution of member -Bhas been effected the plunger will come to the end of groove lc, whichend is inclined outwardly, whereby the plunger is pushed out of thegroove, and thereafter engages for a time with the outer surface4 ofsaid ring, but it has no effect whatever in causing endwise movementofthe member B. By this one revolution of member B, however, duringwhich time said member B is being drawn inward, the dies have taken holdof the work, and thereafter will make their own lead as they cut thethread. The member B will therefore be gradually drawn into the member.Aby the said action of the dies. The member B and the ring E will rotatein unison because of the pins H carried by the ring passing throughholes in the member B. As member B is thus drawn inward, it carries thecam plate with it, and this cam plate will slide along the nut g and begradually turned in the direction which moves the dies slowly outwardly,and thereby they will cut a tapered thread upon the work. When a threadof sufficient length has been cut the cam plate will generally havepassed be ond the nut g into the plane of the body o fthe bar G, or atleast onto the lower tapered end of said nut. When the cam plate is nolonger engagin with the nut,-and perhaps when it 1s em racing thetapered end thereof, the.

cam platemay be turned so as to withdraw the dies from the work. Thisbeing done,

,the work may be withdrawn .from the device, and thereafter the memberB, and cam plate may be moved endwise, without turn,- lng, so as torestore the parts to the position for again beginning to cut a thread.As member N and its ring K are moved outward in member A, the inclinedface lc on ring K will engage the plunger M and push it outward and'hold it out until the groove k comesinto the range of said plun er,whereupon the plunger will snap into tghis groove. As the parts ,moveinto this position the cam plate, by engagement with the taper ended nut'g 'will be turned to the proper position to set the dies for 'beginningthe cutting of a new thread. The enlarged part of the guide bar G ismade in the form of an adjust-able nut, in order that the device may beadjusted to throw oil' the dies at any desired point.

In orderto prevent the chips produced by the dies from getting betweenthe die carrier and work holder, and into the described lead devices, acylindrical chip shield p is provided. It is secured to the work holderby means of a flange p which is clamped between the lowerend of themember a, and a shoulder a2 on 'the membera-and the shieldy fits theinnersurface of the die carrier. I

Having thus described my invention, I claim:

1. In a threading machine, a work holder, a die carrier which isrotatable and movable lengthwise relative to said work holder', a diecarried by'` said die holder, and a cam plate havingv an overhangingedge carried by and f adapted to turn uponV said die carrier and vtocontrol the position of the die a ring rotatable upon the work holderbut Aincapable of longitudinal movement thereon, means compelling thisring and die carrier to rotate 1n unison, an inclined arm secured tosaid ring and 'passing through a hole in the over-hanging edge of saidcam plate, said arm being enlarged in that part which normally plays inthe hole in said cam plate, said enlarged part having a tapered innerend.

f2. 'In a threading maemne, a work holder, a die carrier whichisrotatable and movable lengthwise relative to said work holder, a diecarriedl by said die holder, and a cam plate having an overhanging edgecarried y and adapted to turn upon said die carrier and to control theposltion of the die, a ring rotatable u on the work holder but incapableof longitudinal movement thereon, means compelling this ring and diecarrier to rotate in unison, an inclined arm secured to said ringang/passing through a hole in the over-,hanngfi g edge of` said camlate, said armbeingprovided with a cylin rical enlargement secured forlongitudinal ad- 'ustment on said arm and adapted .to play 1n the holein said cam plate.

3. In a thread cutter, the combination of a tubular work holder, atubular die c arrier rotatably mounted upon rthe work holder and capableof longitudinal movement relative thereto,-the die carrier havin anexternal flange Within the work ho der, and said flange having in itsperiphery a spiral groove with an inclined terminal, and having also' atapered end, with a movable device carried by the work holder and aspring for forcing the same inward whereby it wlll engage with thetapered end of said flange or with the periphery of the flan groovetherein accordmgto the relative positions of the die carrier and workholder.

e or with the spiral- 4. 1n a thread cutter, a work holder comprisingtwo concentric teiescoping arts, the` outer member having an inward yturned flange at one end, a tubular chip shield con- 5 centric with thework holder 4and having an outwardly extended fiange which' is clampedbetween the end of the inner member of the work holder and the inwardlyturned flange on the outer member thereof, combined with 10 a diecarrier having a tubular portion-which is rotatably mounted in the workholder, with its end embracing the cyiindrical portion of the chipshield. A

In testimony whereof, I hereunto affix my signature in the presence oftwo witnesses. 15

HERA N WQ USTER.

Witnesses:

E. JB. Gmcmrsr, H. R. SULLIVAN.

